Was this from the States? Because something related to Prohibition upon alcohol would be my guess. 1920-1933 in the States.

Could also be something about womens’ rights?

EDIT: “!” to “?.” Not sure why I did that.

The banner is wordplay regarding “passed” being able to mean “overtaken on the road” or “defecation”

They’re saying this car slow af (or traffic is bad) XD

I’m pretty sure it’s about being slow, haha.

I’ve seen this bper sticker in recent years, awesome to see it has such a long history!